Buckwheat Greens Toxic?
The surprising answer is a clear and unequivocal YES. Due to the growing
popularity of sprouts in general, and a widespread ignorance as to
the toxic dangers posed by buckwheat greens specifically, many people
are today suffering unnecessarily. In this article I will describe
the toxic effects of ingesting buckwheat greens, and I will answer
the question of why they are toxic to humans. I will also provide a
brief synopsis of what is currently known about this phenomenon. And
finally, I will recount my own anecdotal experience with buckwheat
The basic problem with buckwheat greens is that they contain fagopyrin,
a naturally occurring substance in the buckwheat plant. When ingested
in sufficient quantity, fagopyrin is known to cause the skin of animals
and people to become phototoxic, which is to say hypersensitive to
sunlight. This condition, specifically known as fagopyrism, occurs
when the ingested fagopyrin accumulates under the skin and is subsequently
activated by sunlight, resulting in a toxic reaction within the skin.
Typically, exposed areas of skin turn pink or red within minutes, and
a strong burning sensation accompanies the reaction. Within a few hours
the exposed areas usually appear to return to normal, however continue
to remain ultra-sensitive to cold water, hot water and to friction.
This sensitivity can last for days.
In addition to the burning sensation, people suffering from fagopyrism
often complain of feeling a numb, fuzzy, buzzing impression when they
scratch or inadvertently hit their hands on something. Sufferers also
report that their hands feel painfully cold when placed in cold water
or when in contact with a cold object, even if only for a few seconds.
Some have had numbing, itching and tickling on the face, nose and ears
after sun exposure causing a desire to scratch the skin, thus worsening
the condition. The eyes may also become hypersensitive to light. If
a large enough portion of the skin is exposed, one may experience dizziness.
If a person is forced to remain in the sun for a long period of time,
the skin may swell up and remain abnormal for up to several days.
Fagopyrin is not activated by ultraviolet light but reacts to a different
portion of the sunlight spectrum. Therefore, the normal application
of sunscreen offers no protection at all. Glass, which filters out
ultraviolet rays, does not however filter out the reactive range relative
to fagopyrin. This means that sunlight coming through home or car windows
also causes a phototoxic reaction.
Unlike the shoots of the buckwheat plant, buckwheat groats, or seeds,
are not generally problematic because they contain only trace quantities
of fagopyrin. Buckwheat groats are commonly sold as kasha or are ground
into buckwheat flour, which is used to make soba noodles and buckwheat
pancakes. These foods have long been used as staples in many cultures
and appear to be perfectly safe. The danger lies not in the grains,
but in the mature green buckwheat plants that some animals may ingest,
and in the young green shoots, which increasing numbers of health-conscious
individuals are consuming. These foods contain large quantities of
The phenomenon of fagopyrism is already well known in the field of
veterinary science, where it has been well documented that animals
feeding excessively on buckwheat plants develop skin rashes and other
symptoms. However, little or no research has yet been done regarding
humans and fagopyrism. This is probably because buckwheat greens did
not play a significant role in the human diet until very recently.
No known cultures have relied on buckwheat greens as a staple. Given
the growing popularity of juicing green foods however, along with eating
sprouts and young shoots, many unsuspecting raw foodists and other
health and nutrition enthusiasts have begun to suffer the effects of
fagopyrism. Unfortunately, I am one of them, and my story is a perfect
example of this growing problem.
My adventure began during the winter of 2002, when my wife and I attended
a three-week program at a popular raw food health center in Florida.
I hasten to say that we thoroughly enjoyed the program, made new friends,
soaked up information, took copious notes, and were hopeful that this
new approach to diet and lifestyle would help us to improve the quality
of our life and overall health in general.
Along with consuming raw food, one of the many things the center advocated
was that we drink four glasses of green juice every day. This green
juice was made from equal parts of cucumber, celery, sunflower greens
and buckwheat greens. Following our three-week stay at the center,
we remained on the raw food diet and faithfully drank our four daily
glasses of green juice. A friend also chose to integrate the green
juice into her daily food program. After several weeks, all three of
us began to notice tingling in our hands and faces along with markedly
increased sensitivity to the cold. Given that winter was at its peak
where we live in Quebec, Canada, we thought that our new diet simply
demanded a small adjustment period. Assuming that the natural green
juice program was safe and healthy, we simply failed to make a connection
between the toxic effects we were experiencing and the juice we were
consuming. We thought that adding more fatty foods to our diet would
help us with the cold and the unpleasant sensations would soon disappear.
But they didn't.
Before long our symptoms worsened to the point where any exposed skin
sunburned very easily. I, drinking the most juice, became so sensitive
to the sun that after a few months I could not be exposed to sunlight
for more than a few minutes at a time. The biggest mystery was that
even inside my own home, I could not endure sunlight coming through
the windows for more than three minutes. It made no difference whether
I was inside or outside! Any activity that exposed me to the sun was
threatening—even driving my car! If I tried to go anywhere during
daylight hours, by the time I reached my destination my hands would
be bright red and burning. To manage this, I had to actually put a
towel over them while driving. My wife, who was also drinking the juice,
though less of it, also felt overly sensitive to sunlight and was unable
to stay in the cold without her face and hands itching. Our friend
was also experiencing fuzzy, numbing sensations and exaggerated pain
whenever she lightly bump her hands. She, too, felt that the sun was "too
At the time, we did not have a clue that buckwheat could be the cause
of our strange symptoms. When I mentioned our problems to leaders at
the Florida health center, we were told, "strange things like
that happen when people are starting the diet," and "these
minor glitches will soon pass." I now believe that these problems
eventually do go away for most people—but only when they give
up the new diet, or at least stop drinking the green buckwheat juice.
Back in March 2002 however, still suffering in ignorance, I began to
ask various health advisors and professionals about my symptoms. My
medical doctor thought it might be lupus. Fortunately, the test came
out negative. A naturopath's explanation was that it was "toxins
coming out" and I was having a "healing crisis." He
told me that enzymes in the raw foods were dislodging deep acidic residues
which were then burning the skin. A second naturopathic doctor believed
that something was "toxic in my body," but could not determine
what it was. Yet another practitioner suggested that I was not "detoxing" rapidly
enough, and said that I should add various supplements to my diet.
None of this made much sense to me, and no one seemed to offer a clear
My quest for an explanation lasted many months and was entirely fruitless.
All the while, the three of us remained thoroughly baffled, and were
even more confused by the fact that our skin sensitivity seemed to
improve or diminish every once in a while—for no apparent reason.
We kept telling ourselves, in the words of those at the Florida health
center, "these minor glitches will pass." Now, as I think
back, I realize that our better, less photo-sensitive days coincided
with the times when we had run out of buckwheat greens and had left
it out of the juice for a few days. But back then, in the winter of
2002, we mistakenly believed that others who were eating the same products
were experiencing none of our symptoms. Only later did I discover that
even though these folks were eating lots of raw food, their program
did not include eating buckwheat greens regularly.
After reading that celery contains psoralens, which could cause skin
sensitivity, I stopped consuming it. It never occurred to me that another
ingredient in the green juice could be the culprit. In an attempt to
relieve our symptoms we altered our diet in several other ways. When
I read about high chlorophyll food such as wheatgrass causing skin
sensitivity, we cut that out. I read something similar regarding citrus
fruits and cut them out as well. Alfalfa sprouts are said to contain
caravanine, which is suspected of creating lupus-like symptoms, so
that was also cut out. Someone suggested adding more cooked food to
our diet so we tried that. We stopped eating nuts, seeds, avocados
and quinoa. We drank more water, exercised and had massage therapy.
During this time, I was regularly searching the Internet for answers.
One day, frantically, I did yet another Google search using the words: "skin," "sun," "sensitive," and "burning." Solar
eczema and/or solar urticaria kept coming up, even though it was described
as a rather rare disease. Why would the three of us suddenly develop
a rare disease? It did not make any sense. Online, I found a list of
foods, herbal remedies, and medical drugs that cause photosensitivity
in humans, but we had already eliminated all of the food products and
none of us were taking any medical drugs. All roads led to dead ends;
I was back at square one.
I thought back to the naturopath who believed that the condition was
caused by eating raw food and the subsequent release of acids. Although
his explanation simply was not credible, he had mentioned witnessing
the same phenomenon with other people eating the same way we did. So
I attempted another Google search using the keywords: "raw," "food," "skin," and "sun." The
first link brought me to a message posted in May 2002. It read:
visiting a West Coast Health Institute a year ago, I have developed
a skin sensitivity. My skin burns when exposed to the sun and is very sensitive
to the cold. For example, if I wash my hands in cold tap water, it feels as if
my hands have been in ice water for a long time. My skin is also sensitive to
minor bumps. I have been to a team of specialists and had every test run. The
doctors say it is something in my diet. I eat almost completely raw. My diet
consists of sunflower and buckwheat sprouts, fenugreek sprouts, wheatgrass juice,
and a variety of other green juices, seed cheese, a variety of nuts and seeds
and plant fats. Please help! Has anyone out there had a similar reaction? I would
appreciate any ideas."
I eventually had a telephone conversation with the author of the message. She
had found the cause of her symptoms and did not suffer from it anymore. "It's
the buckwheat greens," she said. While it seems painfully obvious now,
with the information I have, it was the last thing I would have suspected at
It turned out that she had gone through a process similar to mine for about
a year. From the medical doctors, naturopathic doctors to the lupus test, and
finally cutting out celery and other food products. Living in the southern
part of the United States, it was almost impossible for her to avoid the sun,
and she was rushed to the hospital once. In our case, since we were living
in Quebec, most of our skin was covered during a large portion of the year
so we never experienced the massive reaction that she did. She had contacted
some of the top leaders in the raw food movement. They were unable to give
her an answer. Then, somewhere in her research she found a note from David
Wolfe, a prominent raw food advocate, which mentioned something toxic about
buckwheat. She removed the buckwheat greens from her diet and improved rapidly.
She said that within one week her symptoms were gone.
Following her suggestion we eliminated buckwheat greens from our diet, and
within one month the numbing, fuzzy, buzzing feelings in the face and hands
disappeared for both my wife and myself. The adverse reaction to cold or hot
water was also gone. Reddening of the skin took longer to disappear completely
but after two months that problem was gone.
After my telephone conversation, I searched once again with Google, using the
words: "sun," "buckwheat," and "skin." A
lot of information came up. Dozens of websites mention fagopyrism. Among the
most interesting citations was from a message forum written by "Sproutcreek" in
the year 2000:
Date: Thu, 27 Jan 2000
Subject: Re: Skin soreness and photosensitivity
The "tingles"- skin burning easily from sun exposure and a numbness
in the hands accompanied by exaggerated pain if you bang your hand, etc seems
to be common among most people who eat too many buckwheat greens. It was common
among staff and guests at Ann Wigmore's retreat when I worked there.
It seemed like you couldn't eat (chew) enough to cause it, but when you
juiced it or put large amounts in the blender you exceeded you tolerance level
and these strange symptoms appeared. I haven't experienced it or heard
of it with any other greens, but I did get the tingles myself along with most
others from buckwheat. Do you eat buckwheat greens?
My comments: In January of 2000, some people were already aware of
this. It even had a name: "the tingles"! I was surprised
to read that it had been a known occurrence for so long. Why doesn't
anybody talk about it?
There is abundant scientific information about fagopyrism in research
material, including on the Internet. However, nearly all of the references
are relative to veterinary health care because human consumption of
the buckwheat plant is relatively new.
The dictionary on the Internet at http://www.dictionarybarn.com/FAGOPYRISM.php defines fagopyrism as "Photosensitization, mainly in cattle and
sheep, caused by ingestion of buckwheat (Fagopyrum esculentum) and
characterized by irritation of the skin, oedema, and a serous exudate."
It is mentioned in the IVIS document available on the Internet at www.ivis.org A Guide to Plant Poisoning of Animals in North America, A.P. Knight
and R.G. Walter (Eds.) Publisher: Teton NewMedia, Jackson WY. ".
. . Some plants contain compounds or pigments that once absorbed from
the digestive system induce a direct effect on nonpigmented skin when
it is exposed to light . . ."
"Primary photosensitization develops when animals eat plants containing
polyphenolic pigments. These compounds are at highest concentration in the green
plant and are readily absorbed from the gastrointestinal tract to circulate in
the blood. In nonpigmented skin these compounds react with UV light [note: actually
for buckwheat and St John's wort it reacts with another part of the sunlight
spectrum—not the ultraviolet] to produce radiant energy that oxidizes essential
amino acids in the skin's cells. The cells die in the photosensitization
process, and the affected skin eventually sloughs off. Two plants associated
historically with primary photosensitization are buckwheat (Fagopyrum esculentum),
and St. John's wort (Hypericum perforatum). Both plants contain polyphenolic
pigments capable of causing primary photosensitization."
"Clinical Signs of Photosensitization. Photophobia, excessive tearing,
and swelling, redness, and increased sensitivity of nonpigmented skin initially
characterize photosensitization in animals. Affected skin rapidly becomes reddened,
painful, and raised above areas of adjacent pigmented skin. Serum often oozes
through the affected skin to form crusts in the hair. After 2 to 3 weeks, the
necrotic skin becomes dry and parchment-like, and the hair and white skin slough
leaving ulcerated areas that may develop secondary bacterial infections."
Just as indicated in the article, when we stopped eating the buckwheat greens,
all symptoms disappeared. This confirms that buckwheat was indeed the culprit.
Numerous other websites dedicated to veterinary health and medicine mention
From The Identification Guide: Toxic Plants Compiled by Charlie Armour http://www.personalponies.org/DOCS/Poisonous%20Plants_12–09–00.doc:
is cultivated as a crop for fodder and for the production of buckwheat honey.
Eating entire plants, dried or fresh, has caused sensitivity to light in horses
with exposed lightcolored skin. Exposure to the sun is necessary. This plant
is considered to be a primary photosensitizer . . ."
Toxic chemicals: Fagopyrin, probably a derivative of naphthodianthrone, is
closely related to hypericin, which is found in St. John's wort. The
absorption spectra of these chemicals is in the range of 540–610 nm"
THE SUNLIGHT- Wavelength in Nanometers
The absorption spectra is a very important factor in fagopyrism since,
to my knowledge, only these two plants—buckwheat and St. John's
wort—have pigments that will react to this range. Since these
wavelengths are not filtered by glass, the phototoxic reaction will
occur even through a window. This helps confirm that the photosensitivity
is absolutely linked to the ingestion of buckwheat.
From the North Dakota State University NDSU Extension Service
Alternative Feeds for Ruminants AS-1182, September 1999
"Buckwheat grain contains a compound called fagopyrin which can
cause photosensitivity, eruptions on the skin, and itching behavior.
white or lightcolored areas of the hide are affected. The animals apparently
become photosensitive after consuming large amounts of buckwheat for
an extended period of time."
This is particularly interesting since it indicates that an accumulation
of fagopyrin is required to produce symptoms. This corresponds to my
own observation that it took us approximately one month of consuming
buckwheat greens on a regular basis before clearly defined symptoms
began to appear.
The website from the College of veterinary medicine—Colorado
State University http://www.vth.colostate.edu/poisonous_plants/report/report_detail_1.cfm?ID=318 adds a few points: "Animals with white skin are most severely
affected. Black skinned animals are not affected except for showing
photophobia if the eyes are not pigmented. Initially the non-pigmented
skin becomes reddened, swollen and painful. Affected animals become
very agitated when exposed to sunlight often trying to get under vehicles,
buildings, trees to avoid the light.
Diagnosis: Photosensitization. Serum liver enzymes are usually normal,
helping to differentiate primary photosensitization from secondary
photosensitization resulting from severe liver failure."
All of the symptoms arising from the ingestion of buckwheat greens
have other possible causes so it is essential to see your health care
professional to make sure that there are no other underlying causes
or conditions. The parameters of my liver functions were normal, confirming
a primary photosensitization. This means that the photodynamic substance
itself (fagopyrin) in the skin tissues was responsible for the reaction
From The School of Veterinary Medicine University of Wisconsin Madison
Food Animal Ophthalmology Dec. 4, 2002
This article mentions: " . . . some animals may develop blepharitis
through direct solar irritation photosensitization following ingestion
of photodynamic agents such as fagopyrin (buckwheat). Blepharitis is
a condition that causes inflammation of the eyelids. Symptoms of blepharitis
include a burning sensation, excessive tearing, itching, sensitivity
to light (photophobia), red and swollen eyelids, redness of the eye,
blurred vision, frothy tears and dry eye."
I believe that this is worth noting because our eyes felt extremely
sensitive to sunlight, although we never developed any other symptoms
From The Illini PorkNet: http://www.traill.uiuc.edu/porknet/paperDisplay.cfm?Type=paper&ContentID=84
Illini PorkNet. The Online Resource for the Pork Industry. Buckwheat
as a Feed Ingredient in Swine Diets. Gilbert Hollis
The article states: "When exposed to sunlight, pigs fed high
levels of buckwheat develop peculiar eruptions and intense itching
of the skin. This is caused by a photosensitizing agent in buckwheat
known as fagopyrin. Only white or light-colored areas of the skin are
affected, and they must be exposed to direct sunlight. If animals are
kept indoors, they remain normal."
I find this text very significant because it implies that the fagopyrin
develops its toxic attributes only if and when light skin is exposed
to sunlight. Without light to trigger the reaction, the animals remain
normal. This explains the fact that we felt normal except after exposing
our skin to light.
The Canadian Government Biodiversity Information Facility website http://www.cbif.gc.ca/pls/pp/ppack.info?p_psn=231&p_type=all&p_sci=sci&p_x=px has the following notes on poisoning from Buckwheat: Buckwheat (Fagopyrum
esculentum) is cultivated in Canada as a crop for fodder and for the
production of buckwheat honey. Ingesting entire plants, dried or fresh,
has caused photosensitization in animals with exposed or light-colored
skin including cattle, goats, sheep, swine, and turkeys. Exposure to
the sun is necessary. This plant is considered to be a primary photosensitizer,
although jaundice has occurred concurrently, which indicates secondary
involvement of the liver (Cooper and Johnson 1984, Cheeke and Schull
1985). Photosensitization has not occurred in humans (Blumstein 1936).
Little fagopyrin occurs in the seeds, but ingesting the entire plant,
either green or dried, can cause serious photosensitization in livestock
(Johnson 1989). This Canadian Government website has numerous references
and goes on to list all of the buckwheat poisoning occurrences in various
Note that the reference to humans is from 1936. Humans have been eating
the innocuous seeds for a long time but only animals were eating the
raw buckwheat plant in large quantities. However, with the expansion
of the raw food movement and the use of buckwheat greens as a food
source for people, some humans are now experiencing similar symptoms.
The mention of a possible secondary involvement of the liver is worrisome
but to my knowledge does not correlate with any human observation.
Even the FDA poisonous plants database showed 32 different references
relating to buckwheat poisoning: http://www.cfsan.fda.gov/~djw/pltx.cgi?QUERY=buckwheat
There are many other papers and Internet resources that further explore
the effect of fagopyrin. The information provided above represents
a good summary of what's available.
A natural food diet is certainly a good thing, and including a large
portion of raw food also seems like a good idea. Most sprouts are harmless
but powerful superfoods. Sunflower greens, broccoli sprouts, radish
sprouts, fenugreek sprouts, etc. are all excellent products in reasonable
quantities, but ingesting large quantities of these food products is
still somewhat untested and should be done carefully.
I would like to make the disclaimer that I am not advising people to
stop eating buckwheat. The Latin expression dosis sola facet venenum
(the dose makes the poison) attributed to the ancient Romans could
be applied here. A small quantity of buckwheat greens (or buckwheat
lettuce as it is often called) in an individual diet could allow for
healthy nutritional benefits without the negative effects of large
amounts. Buckwheat does contain a large quantity of rutin, a member
of a large group of phenolic secondary metabolites of plants that include
more than 2,000 different known chemicals. Rutin is important because
it strengthens capillaries and so helps people suffering from arteriosclerosis
(the hardening of the arteries) or high blood pressure. Rutin is not
found in beans or other grains such as rice, wheat, etc. but is contained
in a fairly large quantity (4–6%) in buckwheat. Rutin belongs
to a group of plant compounds called bioflavonoids that also include
the important catechins of green tea and the polyphenols of red wine.
Recent studies have shown that the bioflavonoids are powerful antioxidants
which fight free radicals. Rutin is also found in the rind, pulp and
skin of such fruits as lemons, grapefruits, oranges, lime, grapes,
cherries, plums, peaches, apricots, apples, berries and vegetables
such as green and yellow peppers, tomatoes, onions, broccoli, parsley
and especially asparagus. It is also said to be found in bee propolis,
green tea and black tea. (source: http://www.acu-cell.com/bio.html )
I've eaten buckwheat most of my life without any sun sensitivity
problems. I ate buckwheat in pancakes as a child, and later in the
form of kasha and soba noodles. However, while several Health Centers
are suggesting daily green drinks that include a lot of buckwheat greens
for long periods of time, I believe this is risky. At the very least,
people with fair skin should be informed about potential phototoxicity.
Even people with darker skin should be very careful with the unpigmented
flesh around their eyes. Animals consuming large quantities of buckwheat
plant have developed blepharitis, a painful inflammation of the conjunctive
tissues of the eye. It seems possible that blepharitis could occur
Based on the information above, I believe everyone should avoid the
regular use of large quantities of buckwheat greens in their juices.
It is relatively easy to find out if you are intoxicated with fagopyrin.
N.T. Clare in Photodynamic action and its pathological effects states
in 1956 that "no human cases have been reported, although it
may easily be mistaken for sunburn. In this case fagopyrism may be
distinguished by exposing the suspected skin to light filtered through
plate glass which does not allow ultraviolet to pass through." This
is a simple procedure. If you are in doubt, expose a small part of
usually unexposed skin to the sun through a window and use a timer.
If you do not get a reaction within fifteen minutes, most likely you
are fine. A reaction would be a reddening or burning of the skin. If
the reaction is very light you may barely notice it. If, a few hours
later, the exposed skin is itching, abnormally sensitive to the cold
or hot water or if you feel exaggerated pain when your skin is scratched
or hit, you may have a problem with fagopyrism. If the symptoms disappear
after removing buckwheat from your diet, this would confirm that it
was causing the symptoms.
I believe that a lot of buckwheat greens eaters have these problems
to some extent. A friend of mine recently told me that the sun had
become much stronger and very unpleasant, probably because of the ozone
layer. I think that the real cause of his discomfort is that he eats
a lot of buckwheat greens. Another man says his hands have become very
sensitive to the cold and he thinks he might have Raynaud's disease.
But he also eats a lot of buckwheat lettuce. Another friend works outside
in a field. She recently started to eat a lot of buckwheat greens that
she grows herself and began to complain about burning sensations on
her hands and strange feelings on her face, as if she had no skin anymore.
When she stopped eating buckwheat greens, everything returned to normal.
As this information circulates, I believe that many people will identify
buckwheat as a possible cause of their symptoms.
I still eat a lot of sprouted foods myself. I believe that the center
I visited on the East coast does very good work overall. I've
witnessed many people improve their health considerably during the
time I spent there. I've also seen that the leaders manifest
a high degree of flexibility and open mindedness about modifying their
approach when presented with new information. I'd love to return
there myself to enjoy their facilities again sometime.
While I have been an enthusiastic natural food consumer and researcher
for 35 years, I am not a medical professional nor a scientist. This
article is based on my experience and research and represents my opinion
only. Please do not consider this article to be medical advice. I strongly
urge you to consult your health care professional for any symptoms
you may have. Be sure to get a blood test for your liver functions.
If your liver function test results are normal then you probably suffer
from primary phototoxicity, meaning that it is the photodynamic pigment
itself in your skin that reacts to the sun and that you likely do not
suffer from a functional disease. This is exceedingly good news since
the solution is simple: just avoid the causative substance.
I have done this research in good faith to help myself and my friends
with our problems and I believe these findings may be useful to others.
This is why I am making this document available. I have nothing to
gain from it personally. I am not associated or affiliated with any
agency, school, company or organization that could benefit in any way
from this information.
Updates and forum board at http://www.gillesarbour.com/